Muslim jurists agree that the wife is permitted to wash the body of her dead husband. The same permission is granted to the husband in washing his wife’s dead body according to the most correct opinion as inferred from the sources.
In his well-known book, Fiqh As-Sunnah, Sheikh Sayyed Sabiq states: “Muslim jurists agreed on the permissibility of a wife washing the body of her dead husband. `A’ishah (may Allah be pleased with her) said: “Had I known then what I know now, I would not have allowed anyone, except his wives, to wash the body of the Prophet.” (Reported by Ahmad and Abu Dawud and al-Hakim)
There is a difference of opinion, however, on the permissibility of the husband washing the body of his dead wife. The majority of scholars, nonetheless, consider it permissible, as is shown by a report, narrated by Ad-Daraqutni and Al-Bayhaqi, that `Ali (may Allah be pleased with him) washed the body of Fatimah, his wife, on her death. This is also supported by a hadith that the Prophet (peace and blessings be upon him) said to his wife `A’ishah: “If you die before me, I will myself wash you and enshroud you.” (Reported by Ibn Majah)
But the Hanafi school of Fiqh holds that it is not permissible for a husband to wash his wife’s dead body, and if there is no other woman available then he should give her tayammum (dry ablution). However, the above hadith proves the contrary of this view.”
Commenting on this second opinion and the claim that the relationship between spouses is severed by the death of one of them, Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states:
“There is no solid basis for such an interpretation. The Prophet (peace and blessings be upon him) had remarked to `A’ishah prior to his death: “If you were to die before me, I would have washed you, shrouded you and prayed over you.” (Reported by Ibn Majah, Ahmad and An-Nasa’i).
It is generally known that it was `Ali who washed his wife Fatimah, the daughter of the Prophet (peace and blessings be upon him). (Reported by Al-Bayhaqi, Al-Daraqutni, and Ash-Shafi`i). `Ali was well known for his deep knowledge and understanding of Fiqh; and as such it is unlikely that he would have been ignorant of such a crucial piece of information.”
Excerpted, with slight modifications, from:
Regarding the permissibility of a wife washing the body of her dead husband, Sheikh M. S. Al-Munajjid, a prominent Saudi Muslim lecturer and author, adds:
“The wife has the right to wash her dead husband. In his book Al-Muwatta’, Imam Malik narrated on the authority of`‘Abdullah ibn Abi Bakr that Asma’ bint `Umays washed Abu Bakr As-Siddiq when he died, then she went out and asked the Muhajirin (the Prophet’s Companions who migrated from Makkah to Madinah) who were present, “I am fasting and the day is very cold; do I have to do Ghusl (bath)?” and they said, “No.” (Al-Jana’iz, 466)
The author of Al-Muntaqa `ala Sharh Al-Muwatta’ said concerning this hadith: “This indicates that it is permissible for a woman to wash her dead husband, because this happened in the presence of a number of the Prophet’s Companinos, especially since Abu Bakr had left instructions in his will to that effect. No record of any dissenting Companions of the Prophet on this matter. So this shows that there was consensus.”